The Digital Fix: Film

Toshiba engineer speaks about HD DVD

As part of the upcoming IFA consumer electronics show in Berlin, DVD Times got the chance to talk with a Toshiba engineer regarding HD DVD.

The area of expertise of the Toshiba employee we spoke to was in the disc drives themselves. This is a separate division to Consumer Electronics - the people that manufacture and design the actual players.

Nonetheless, Toshiba told us that we can expect more news regarding the European launch of HD DVD on Friday, although the interview contains some information about what to expect from the player (an adapted version of the excellent American player, and not a second-generation model). The not yet official word is that we shouldn't be too surprised if we hear the players will be in shops in October.

The rest of the interview contains some very interesting in-depth information about the HD DVD format itself, and how the discs are constructed and read, especially in contrast to Sony's Blu-ray. The entire interview is available here as an 8.35mb MP3 file, but for those of you who prefer to read, we have a transcript below.

DVDTimes: The first question was - when can we [expect to] see the first European HD DVD player?
Jim Armour, Toshiba: That will be shown at IFA beginning on Friday this week, in Berlin.

Just a little background information - I'm not actually with the consumer group at Toshiba. I'm with the storage device division - we just make PC drives. I'm not quite sure when they're actually shipping this, but I believe it's sometime in October.

What we're actually doing right now with our drive - which is a slimline HD DVD/DVD Combo drive - so it'll read HD DVD, DVD, CD, and actually write DVD and CD as well - they're actually shipping that in a notebook PC called the Qosmio G30. I believe they're shipping that product now.

DVDTimes: The second [question] then would be - is it just Toshiba that's bringing out players, or are there any plans for other manufacturers?
Jim Armour, Toshiba: Well currently, it is only Toshiba. However, there are other manufacturers who are Toshiba affiliates. There is one other company shipping - I think it's RCA.
DVDTimes: That's right, yeah. I think in America, they've got a rebranded one. It's a clone.
Jim Armour, Toshiba: Exactly, yeah, a rebranded one. This might happen in Europe as well.

DVDTimes: Do you know how much the European player is going to cost when it first arrives?
Jim Armour, Toshiba: I don't [...] because we have different VAT in different countries and we have to cope with VAT, but you could probably say something in the region of... I can't really say, because it would just be speculation. I'll find out on Friday. [...]

They're shipping it in the States for $499. It'll probably be something like that here, but in Euros.
DVDTimes: So a rough equivalent you think?
Jim Armour, Toshiba: Yeah, I think it'll be a rough equivalent, dollar to Euro, so maybe 599 Euros or something.
DVDTimes: I think I read on the AV Forums, some French site is advertising it for - I think 600 Euros.
Jim Armour, Toshiba: With local VAT, it'll probably be around 600 Euros, but on Friday it'll be official.

DVDTimes: Also, what about regional coding? As I understand it, right now, there's been no regional coding set for HD DVD itself.
Jim Armour, Toshiba: That's correct.
DVDTimes: So, when the first European movies arrive, will all the people that imported American players - and people in America - should they be able to play back the European titles with no problem?
Jim Armour, Toshiba: They should be, yeah. Well, Europeans play back American titles and Japanese titles - and European titles. We're only concerned with the European market. I've not been told that European titles would be region coded, exactly the same as the Japanese and American [ones] - at this moment in time, anyway.

DVDTimes: That brings me on to another question - I think it was Studio Canal - they said that their first HD DVDs are going to be in 24p format, so basically, American friendly. Have you heard anything about that?
Jim Armour, Toshiba: Well, 24 frames per second is actually the movie standard, and it is part of the HD DVD format. We can actually play back 24p, on any [HD] DVD player that's not region coded. That's not an issue at all.
DVDTimes: Do you think [24p] will become the standard for films on HD DVD in Europe, or will any studios be doing the usual "PAL" speedup?
Jim Armour, Toshiba: I think a lot of the studios - when they recode - they do PAL speedup, most of the time, so you get 25 frames per second here most of the time. I have a title that's 24p, and that plays back on everything - an expiremental title. It's a case of "they'll decide" - studios decide what they want to do. If they support the format and hardware, they'll just do it. I think they'll either stay with 24p or go with 25 frames per second.
DVDTimes: So it could really end up being a mix.

DVDTimes: Someone also asked... right now, the American version of the player - I'm not sure how similar that is to the version you'll be releasing in Europe? Is it going to be an adaptation of that? Or is it going to be completely new, second-generation stuff?
Jim Armour, Toshiba: No, it's the HD-_1, as it's already known.
DVDTimes: So it's the European adaptation of that, basically?
Jim Armour, Toshiba: Exactly, yeah.

DVDTimes: Well, the American version, obviously, for standard-def it only plays back Region 0 and Region 1 NTSC discs. I think this is less of a problem in America where there's a smaller take-up of multi-region stuff - but a lot of people in Europe have been asking, will there be any way to remove the regional lockout from the standard-def DVD [playback]?
Jim Armour, Toshiba: (Laughs) No. I know of no way at all. If I was to say "Oh yeah, you just have to press these buttons"... coming from Toshiba, that would be - illegal! I'd lose my job! Thank god I'm in the storage device division that makes drives and not the divison that makes consumer players. There'll be a way of course, it'll be possible no doubt - but I'm not aware of it at all.

DVDTimes: Moving onto the questions about the format now. Reading AVSForum.com [in America], there's some rumours going around about the actual capacity of the discs. I think NEC have announced a new drive for PCs, and that can supposedly read the triple-layer 45gb discs.
Jim Armour, Toshiba: Even although the disc is not ratified yet by the [DVD] Forum?
DVDTimes: That's what I was going to ask you - what's happening with that. Is it likely we'll see a 45gb disc out?
Jim Armour, Toshiba: The triple layer disc is not actually due out until next year. I believe that the actual book type will not be ratified by something like June next year [2007]. So, announcing they can read triple layer is very odd.
DVDTimes: It'd have to go through the DVD Forum, wouldn't it?
Jim Armour, Toshiba: Yes, definitely. The version of the book we're on now is something like 0.4, which is a very early stage. Until the actual format is approved by the Forum, we're expecting about another four months for it to go through. And then, they'd upgrade the book to 0.8. Then, they do physical layer testing and things of that nature, so we're expecting the book type to be released probably mid-next year.
DVDTimes: So, if that does come out, do you know if the current drives would be able to read it with a firmware update? Is there any likelihood that we'll ever see triple-layer film discs?
Jim Armour, Toshiba: Any likelihood... well, if we're actually creating the format, I think there's a likelihood. There is a likelihood - a 45gb capacity could be very useful. Whether drives can read it, I don't know - because, basically the specification hasn't been set. It's like when the first Dual Layer DVD-Rs came out, really old drives couldn't read it. [...] It could well be the same situation. Until the standard has been specified and ratified, you can't really say whether it'll be able to read it.

I would go as far, in fact, to say probably not. You're having to focus through two primary layers. The amount of reflected energy that you're going to get back will be quite low. Now in my opinion, in order to read this kind of media, you're going to need something like - do you know your way around the term PRML?

DVDTimes: I actually don't, no - could you explain that?
Jim Armour, Toshiba: It's Partial Response Maximum Likelihood - PRML. It's in hard discs. It's like a digital filter where you take the signal, which is quite weak and has a lot of noise in it, and you clean up the noise. The signal you get out is still looking like noise, but you know that in certain points, the data is going to have a slightly stronger signal at these points. So, you put it through a digital filter, and you compare it to non-data. And then, you pick out the data from this noisy signal with it. It's a very interesting technology, but it's not actually built into current HD DVD readers.

The signal that you're going to get back off triple layer is going to be something in the region of only 15-20% of the current reflected information that you get off a single layer.
DVDTimes: Basically, not good enough to get anything out of, then?
Jim Armour, Toshiba: Not good enough to get information out of, WITHOUT this PRML circuitry, and the first drives don't have PRML circuitry built in. I don't think that even with a firmware upgrade, you'd be able to do it.
DVDTimes: Right, it's physical hardware then?
Jim Armour, Toshiba: Yeah, I think second or third generation hardware - fine, but not first-generation products.

DVDTimes: Next question then. Does Toshiba see downloadable films as any kind of threat to physical disc formats?
Jim Armour, Toshiba: Not really. Not at this stage - not without lots and lots of high bandwidth home connections. We're talking about 16 megabits per second, and even then you're going to need something in the region of - with current technology - about 8 hours to download. So, it's going to take a fair bit of time. Actual streaming of the data - not at this moment in time. Downloading, watching twice and then having it erased, or whatever - yeah, that's going to happen, but not on HD at this moment in time. Especially not with the kind of bandwidth that we've got at home in Europe at the moment.
DVDTimes: How about in Japan? Is it a possibility there?
Jim Armour, Toshiba: I think so. Approximately 30% of the United States is still on analogue modems [...] Japan is more advanced. I don't think it's a threat. HD DVD does have the possibility to order extra online content through the DVD.
DVDTimes: Yeah, I think the latest firmware added that option (for the set-top player).
Jim Armour, Toshiba: Yeah, exactly. I think that'll be much more popular than downloading a movie.
DVDTimes: As well as that, personally, I like to own the physical disc myself. I don't know about everyone else...
Jim Armour, Toshiba: Likewise, yeah. I'm the same. If you want to watch [a disc] now, [waiting for downloads] is a bit of a pain. I think it's a possibility once we go into higher bandwidth, maybe 64 megabits per second, or something of that nature. Once we actually get some kind of advanced high-speed internet at home, but not with current speeds that we're looking at.

DVDTimes: Personally I know the answer to this myself, but for anyone that's going to be reading the [transcript], could you explain why the VC-1 codec has become the choice for HD DVD? I think all the titles released so far in America use it.
Jim Armour, Toshiba: You're absolutely right, actually it's not the main choice. It's one of two main choices. We have H.264, which was the primary choice, believe it or not - because a lot of it belongs to us.
DVDTimes: I think in Japan actually, most of the discs are still using that.
Jim Armour, Toshiba: Yeah, that's right, if you look at the titles in Japan, there's a lot of Toshiba - or Toshiba affiliates - written on the back. Basically for Japan, H.264 was the one of choice.

The choice in America of course... Microsoft has endorsed this. And, in the early days, we've seen that VC-1 is a nice codec, it's also very scalable [...] it's a derivative of [Windows Media 9], and it's fine. [...] Getting the big guys on board to endorse it, I think it was more or less a political decision - we're just speculating - and H.264, a lot of that's held by Toshiba, so we decided to use that in Japan, and VC-1 in the States, because we also use iHD - from good old Microsoft - for our navigation and stuff, rather than Java, as the Blu-ray people did. Getting that kind of endorsement from a company like that, is worth quite a bit to us. As you said yourself, you see the country split - VC-1 in the States, H.264 in Japan...

DVDTimes: And it's likely to be VC-1 in Europe, isn't it?
Jim Armour, Toshiba: It's probably likely to be VC-1 in Europe. Either that, or they'll do a split by studio, or whatever - until we see the titles, we'll just be speculating, I guess. It could be a mixture.
DVDTimes: I think, so far, that really has been the main reason why the HD DVD movies look so much better than Blu-ray ones.
Jim Armour, Toshiba: That's what people have been writing as well, actually. In order to get the kind of, let's say, brilliant density, colour, sharpness etc etc, BD [Blu-ray] has to output at near it's maximum bit-rate of 40mbps, and that puts a lot of overhead on the player as well. Of course, the CPU load is very high, and once you start playing around with stuff like navigation, and you're doing it in plain old Sun Java, you do get a few problems.

DVDTimes: Yeah, the first reports of, in particular, the Sony titles, haven't been very good at all, with macro-blocking, banding and the like. When you said that [VC-1] was one of two main choices, I guess MPEG-2 was just put in the HD DVD spec for backwards compatibility more than anything else?
Jim Armour, Toshiba: That's correct, yeah.
DVDTimes: It wasn't really ever considered for HD movie discs?
Jim Armour, Toshiba: Not really, HD movie discs, of course, you can now make HD HOME movie discs using an HD camcorder. The one HD camcorder that's out there does do that, but most of the time using 720p anyway, so the bandwidth is not so huge, therefore it's acceptable. Definitely not for movies - that's never really been acceptable for HD DVD. As you said yourself, MPEG-2 is there for backwards compatibility. We will play back high-def MPEG-2 content if we have to, but it's not the codec of choice.

DVDTimes: If you're not with the consumer division, I'm not sure if you'll know this or not, but is Toshiba actively trying to get greater support from other consumer electronics companies and movie studios?
Jim Armour, Toshiba: Well, yeah, of course. Not just Toshiba, but the DVD Forum is trying to get more support. They have people set aside from Toshiba and other companies to do this - people who work for the DVD Forum who are actively promoting HD DVD. At Toshiba, we're going after customers for our drives. We've got a few nice names in there at the moment.

We're doing it actively here, from a sales situation, also from the DVD Forum's side - people constantly visiting the movie companies, constantly visiting the media production companies, and trying to get them to move over to HD DVD - which is of course much easier than it is for Blu-ray. They can just modify their DVD production line.

DVDTimes: Is there any truth in the rumour - I don't know if it's a rumour or not - that you can change a standard DVD production line over to HD DVD in a trivial amount of time?
Jim Armour, Toshiba: Absolutely true - and vice versa. Once you've modified it, you can actually just throw a switch and change it back. It's absolutely true.
DVDTimes: Whereas Blu-ray would need completely new facilities?
Jim Armour, Toshiba: That's absolutely correct.

In fact, to produce a master for a HD DVD, you need basically a laser beam recorder, just like you need with a normal DVD. That's when you make the gold master. But Blu-ray needs an electron beam recorder, and they cost approximately $1.5 million. And then, the whole moulding process is completely different for them. Whereas, basically, DVD production is two 0.6mm [platters] glued back-to-back to make a DVD. It's exactly the same for HD DVD. That's why there's less cost.

DVDTimes: I think I heard something about Blu-ray discs - I don't know if you know about the difference between the two precisely - is it true that HD DVD would have greater resistance against scratches? Am I right in saying that on the Blu-ray disc, the data is in a different place?
Jim Armour, Toshiba: Well, actually, if you look at the structure of a Blu-ray disc, it's actually 1.1mm thick acro, like a CD. Then you have 0.1mm hard coating on top of that. And the data is actually RIGHT under the 0.1mm hard coating - it's actually more or less steamed onto the polycarbonate under this hard coating. So, the focus of a DVD lens, once you get through the polycarbonate material, it actually focuses 0.1mm onto the actual data layer. The problem with Blu-ray is that the lens is actually positioned 0.1mm above the physical disc. This protective layer on the top of the Blu-ray disc is 0.1mm thick, and is very hard - extremely hard material. It's a very solid carbon material, but transparent. Now, I only know one nearly transparent carbon material, and that's diamond - so, nearly as hard as diamond, very close to diamond. And, the glass lens only floating 0.1mm above it. 0.1mm is about the thickness of four A4 pages of normal paper. So, the reason they made this coating very hard, of course, is because if something hits it, it shouldn't scratch. It can only focus 0.1mm under the surface of the media, where the data is. If you get a scratch, a fingerprint, or a hair, it's going to be unreadable. That's why they made it this way.

DVDTimes: I've also heard that the protective layer is part of the trouble the Blu-ray camp is having in getting the dual-layer discs to work.
Jim Armour, Toshiba: That's exactly correct, because the second layer. The lens on the BD system has a numerical apeture of 0.85. This means that the light cone that's focusing on the disc underneath it, is very wide. It's like the difference between a normal ice-cream cone, and spreading out the top of an ice-cream cone to five times it's physical diameter, and then shortening the length of the cone by about four. So, you've got a very wide cone, focusing on this thing, and it's only going a tiny bit into the media, so if you have dirt or dust or a scratch, or anything like that [...] you're going to have a problem. This is why they had to make it very hard, and they also had to make it fingerprint resistant, so it would repel oil.
DVDTimes: I think in the early days in Japan, they originally had it in cartidge?
Jim Armour, Toshiba: They did, exactly. This is before they put on the hard coating. Blu-ray really needs the hard-coating, but HD DVD doesn't, because our lens is sitting 1mm above the media, and it's focusing 0.5mm into the media, it's focusing right through the media, so we can get a better signal back.
DVDTimes: So basically, HD DVD is more resistant...
Jim Armour, Toshiba: It's more resistant, and more physically reliable. But, the Blu-ray guys [...] they haven't coated the lens with an ultra-hard material, so if the ultra-hard material hits the glass lens, you're going to scratch the lens - then you won't be able to read anything.

DVDTimes: I think the Blu-ray camp was - I wouldn't say promising, but I've heard on a replicator's site, was saying in the future they might be able to get 200gb discs, which certainly seems a bit ...
Jim Armour, Toshiba: A bit daft.
DVDTimes: ... a bit laughable right now when they can't get two layers working.
Jim Armour, Toshiba: They can't get two layers working, that is the first problem. Theoretically, there's red systems [Systems that use a red laser, like current standard-def DVD] based on normal DVD, from niche companies, where you can get 60gb on a DVD. That's not a problem, it can be done, because you use something in the region of eight layers.
DVDTimes: Where was that system from? It wasn't India, was it?
Jim Armour, Toshiba: I saw it a CEBIT this year, I can't remember the name of them. It started with a P.
DVDTimes: It's some kind of competing technology that's going to be used in a different part of the world.
Jim Armour, Toshiba: They basically took red DVD [Standard Def DVD] to multi-layer, and any player can read it, according to them, with a firmware change.

We're going for triple layer [with HD DVD], the feasibility studies have started, we've done it in the lab, we just have to write up a specification. So that'll be at around the middle of next year. It's been proved that it can work, just like dual-layer, for blue, it's been proved in the lab that it can work. But it's a case of getting your reading technology to be able to identify between a signal and noise. This is where this PRML thing (that we talked about earlier) comes in. It's using hard disc technology on optical media. It's the next step.

I agree, they can go to multi-layer, but they're going to have major problems because the signal that they get reflected back is much lower than the signal that an HD DVD gets back.

DVDTimes: And really HD DVD's reliability, it's [because] it's an extension of existing DVD, it's been built on top of it - is that right?
Jim Armour, Toshiba: Exactly right, yeah. I mean, we've been criticised for this. Some analysts went and wrote, Well, Blu-ray is a real innovation, so it's brand new, it's innovative, [but] HD DVD is only an evolution of red. And I agree totally.
DVDTimes: And it turned out to be a good thing in the end.
Jim Armour, Toshiba: I think we human beings have done pretty well over the last million years (!)
DVDTimes: Laughs
Jim Armour, Toshiba: Unless of course you're a creationalist and god created man ten thousand years ago. I think we did evolve from apes and we've done all right! Evolution is OK, it's a tried and tested technology taken to the next level.
DVDTimes: Yeah, I agree completely. As I said, I own the HD-A1, and it kind of speaks for itself.
Jim Armour, Toshiba: Oh, you do? I know it's a bit slow...
DVDTimes: It's slow to boot, yeah.
Jim Armour, Toshiba: Slow at starting.
DVDTimes: But at least the picture quality's there.
Jim Armour, Toshiba: I've read on an American site, in fact, that even when it upscales normal DVDs, the quality's damn good.
DVDTimes: It's a really good upscaler as well, yeah.
Jim Armour, Toshiba: I look forward to getting mine - I'll talk to a few people and see if I can borrow one for a year or so.
DVDTimes: (Laughs) and a big step-down.

Jim Armour, Toshiba: Yeah, it's an evolution, and we're quite happy with that. A lot of this "format war", in inverted commas, is politics. Patents and licenses are a good way to make money. Sony, however, does like to be pretty exclusive on the patents and licenses they have, they've made a damn good living off that for the past 30 years or so. The DVD Forum does not actually give them a lot of opportunity to make the kind of exclusive license money that they'd like to. So, of course they have to go out and make a completely new format.

Both formats were proposed to the DVD Forum. The DVD Forum actually did choose AOD - which is the Toshiba name for ...
DVDTimes: ...for what became HD DVD.
Jim Armour, Toshiba: Both were proposed, but AOD - the Advanced Optical Disc - was accepted, and it's now HD DVD.
DVDTimes: That's interesting - I must have been wrong then, because I read somewhere else that Sony didn't even submit Blu-ray to the DVD Forum.
Jim Armour, Toshiba: They did. Basically, with the DVD Forum - we don't own everything on HD DVD. [...] As far as the media format is concerned, we don't really have any licenses on that. I think we do on the error correction, or something. We only have lisenses on certain parts of hardware, and of course the video codec which is being used. Blu-ray is now using AVC as well, and they'll have to pay licenses on that too. As far as physical formats are concerned, the spacing, the writing method, and things like that, Sony basically wants everything under Sony. The DVD Forum would not accept that. "Not proposed" - not necessarily. If they got at least 40% of the patents pushed through, they'd be doing fine thank-you-very-much.

DVDTimes: So, the issues with patents and licensing - does that go any of the way to explain why the current Blu-ray players are so much more expensive?
Jim Armour, Toshiba: I don't know really. I know past licensing conflicts in the Forum, I get that from my Japanese colleagues, but, why it's that much more expensive... I think it might have something to do with the history. They started selling Blu-ray recorders at something like $4000 about 15-18 months ago - before there was really anything else, to say, "we've got a couple of hundred out there".
DVDTimes: That was the version that used the cartridge around the disc.
Jim Armour, Toshiba: That's right, exactly. And they couldn't just come down and make it $500 when they were charging $4000 - and if they can get it, damn right. Somebody on the internet did a breakdown of the cost of the Toshiba [HD-A1], and they had an estimate of what it was actually costing. They said, Toshiba's paying $150 for each unit - how many dollars do you think Sony's going to be paying towards the PS3?
DVDTimes: (Laughs) well...
Jim Armour, Toshiba: That's going to hurt them big time. We read on the internet, a couple of pages, people estimated it's going to cost them [...] a lot of money. They're putting their money in there.
DVDTimes: I think the console way has usually been to sell at a loss and make it back on software.
Jim Armour, Toshiba: That's exactly right, probably every single game that's going to come out for that console will be on Blu-ray disc, and Sony will get a piece of the licensing for Blu-ray disc, and also for the game of course. For every physical disc that's sold, they'll get money from that as well. I think they consider this more important. [...]

DVDTimes: OK, I guess this, then, would be the last question - could you just tell us again, why you think HD DVD would be the better choice?
Jim Armour, Toshiba: Blu-ray's been pushing the studios to boycott us. I mean, we know that. But the studios are more are less open and have said, "We'll support both - go with whoever wins, we don't care so long as we can get our content out there." We know for a fact that - and it is a fact - that to produce an HD DVD, it's much cheaper than to produce a Blu-ray disc. So basically, the content manufacturers, apart from those that are bound to the Blu-ray Consortium, basically, they're welcoming it. It's cheaper to produce. We did enter the market lower, as far as players are concerned, than BD, and I think we'll continue to do this, because we have the opportunity to produce it cheaper. And we're giving this [reduction] to the customer. And basically, if the customer is getting a decent amount of media at the right price, that does exactly the same as the more expensive system -
DVDTimes: If you don't mind me correcting, so far, it's actually been better than the more expensive media.
Jim Armour, Toshiba: Well, yeah I'm being conservative. They're not producing VC-1 and AVC at the moment because it's going to cost them licensing fees, but sooner or later, they will. They've [the studios] already got it encoded in that format, and all they have to do is port it across, and do the physical writing, and that's it, so they will do eventually - and then, you shouldn't see any difference. The fact of the matter is that it's got to be pressed, and to press a Blu-ray disc, you need to press five layers of different types of materials - it's a very expensive process, like building a layer cake. With HD DVD, you make your two substrates, you spin on your content, and you press it - the same as DVD. It's cheaper to make, it's quicker to make, it's easier to make. When the media came out in the States, I went and bought "The Last Samurai" for $16.99, on HD.
DVDTimes: I can't remember how much we've been paying for the discs so far. It's really been the same price as standard DVDs.
Jim Armour, Toshiba: That's right, and that's good news for the consumer - whereas Blu-ray's supposed to cost about $4 or $5 more - this is what I've seen at Amazon and stuff - so it's about the same price. In Japan, another thing I think's grand - a lot of the discs in Japan are actually twin format.
DVDTimes: That's right, some in the States as well.
Jim Armour, Toshiba: Just stick it in a normal DVD player and watch it, and when you've got enough money to buy yourself your [HD], just turn it around, slap it in - or if it's dual, just slap it in. Dual has a 15gb dual layer and a 4.7gb red layer.

DVDTimes: The titles that we've had so far that have been on a combo format, they've had an HD side that's 15gb - only a single layer so far. I think I read that that's going to be sorted, so it's going to be dual layer HD as well as dual layer DVD on the other side.
Jim Armour, Toshiba: That's correct, that's going to happen. Because the DVD format is already defined. Pressed media, double-sided, double-layer - so we take that and we make one side blue [HD] and one side red [SD]. The format already exists on normal DVD, it's just that it was a wee bit too expensive to make and no-one required it up until now. On HD format of course, it could become very interesting.

DVDTimes: Did the Blu-ray camp have a similar idea with the combo discs?
Jim Armour, Toshiba: Well the combo discs - it would be illegal - because one side would be DVD compliant, wouldn't it? They'd have to ask the DVD Forum for permission. Another thing is, their physical format doesn't allow it, because their media is actually 1.1mm thick acro, with a 0.1mm hard top coating - so what are you going to put the back layer on?
DVDTimes: Right, no room left.
Jim Armour, Toshiba: DVD is two times 0.6mm discs glued together - whether it's HD DVD or standard DVD, they're both 0.6mm polycarbonate discs, glued back to back. Blu-ray is different - 1.2mm plus 0.1. So, it's physically impossible, using their registered format, so they'd have to go with DVD format, which would mean problems with the DVD Forum - because DVD Forum has the patent on 0.6mm times two.
DVDTimes: Ah right, right. Patents again.